Field of the Invention
Embodiments of the present invention relate to a liquid crystal display device. More particularly, the embodiments relate to a column spacer for maintaining a cell gap of a liquid crystal display device.
Discussion of the Related Art
Owing to advantages such as good portability and low power consumption by low operating voltage, a liquid crystal display (LCD) device is widely used in various fields of notebook computer, monitor, spacecraft, aircraft, and etc.
The LCD device includes a lower substrate with a thin film transistor formed thereon, an upper substrate with a color filter formed thereon, and a liquid crystal layer formed between the lower and upper substrates. Also, a column spacer, which is used to maintain a cell gap between the lower and upper substrates, is formed between the lower and upper substrates.
Hereinafter, a related art LCD device will be described with reference to the accompanying drawings.
FIG. 1 is a cross sectional view illustrating a related art LCD device.
As shown in FIG. 1, the related art LCD device may include a lower substrate 10, an upper substrate 20, and a liquid crystal layer 30 between the lower and upper substrates 10 and 20.
Although not shown, on the lower substrate 10, there is a thin film transistor and a pixel electrode. Also, a lower alignment film 15 is formed on the uppermost surface of the lower substrate 10.
Although not shown, on the upper substrate 20, there is a color filter. Also, a column spacer 22 for maintaining a cell gap is formed on the upper substrate 20, and an upper alignment film 25 is formed on the uppermost surface of the upper substrate 20. An initial alignment of the liquid crystal layer 30 is controlled by the lower alignment film 15 and the upper alignment film 25.
However, the related art LCD device may have the following disadvantages.
The column spacer 22 is fixed to the upper substrate 20, however, the column spacer 22 is not fixed to the lower substrate 10. If an external force is applied to the related art LCD device, the column spacer 22 may be moved by the external force. Thus, the lower alignment film 15 formed on the lower substrate 10 may be damaged due to the column spacer 22 moved by the external force. If the lower alignment film 15 is damaged, the alignment of the liquid crystal layer 30 is not controlled so that problems such as brightness defects occur.